Water-Soluble Acrylate Binder for Graphite Electrodes in Lithium-Ion Batteries

Water-soluble acrylate (AcrylS020) was tested as a potential binder for graphite negative electrodes in lithium-ion batteries, and the results were compared to the commonly used carboxymethyl cellulose (CMC) and styrene-butadiene rubber (SBR) CMC+SBR binder combination. Similar performance was observed at low C-rates and room temperature with both binders in Li/graphite half-cells. However, at high C-rates and/or low temperature, better results were obtained with Acryl S020 and the difference at room temperature and 1C was 166 mAhg^-1 vs. 92 mAhg^-1 (AcrylS020 vs. CMC+SBR). The stability of the electrodes was similar in graphite/NMC (LiNi_1/3Mn_1/3Co_1/3O₂) full-cell tests. The structures of the electrodes using different binders were slightly different as evidenced by SEM images. These results indicate that the Acryl S020 binder is also applicable for graphite negative electrodes and can tolerate the volume change of graphite during charging/discharging.